9-9-09 Synaptic Transmission I

9-9-09 Synaptic Transmission I - SynapticTransmission...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Synaptic Transmission Synaptic Transmission Dr. McKemy 9/09/2009
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
http://www.hhmi.org/biointeractive/media/molecular_mech-lg.mov http://www.hhmi.org/biointeractive/media/molecular_mech-lg.mov
Background image of page 2
Synaptic Transmission Synaptic Transmission This is cell-to-cell communication that proceeds in one direction. Occurs at synapses : site where two cells come in contact. When an AP arrives at the axon terminal of a presynaptic cell . Local increase in cytoplasmic Ca 2+ triggers fusion of synaptic vesicles . Neurotransmitter is released into the synaptic cleft . Binds to specific receptors on the postsynaptic cell .
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Sequence of events involved in transmission at a  Sequence of events involved in transmission at a  typical chemical synapse typical chemical synapse 1. Transmitter is stored in synaptic vesicles. 1. An AP enters the presynaptic nerve terminals. 1. Depolarization opens voltage- sensitive Ca 2+ channels. 1. The influx floods the terminal with Ca 2+ . 1. The Ca 2+ causes the synaptic vesicles to fuse with the membrane. 1. Release the transmitters.
Background image of page 4
1. Transmitter diffuses across the cleft to the postsynaptic cell membrane. 1. Transmitters binds to their cognate receptors. 1. Postsynaptic ligand (transmitter) gated ion channels open or close. 1. The postsynaptic current can be either excitatory or inhibitory. 1. This current changes the excitability of the cell. 2. Excitatory leads to depolarization and AP generation. 1. Increase in tonic activity 3. Inhibitory leads to hyperpolarization. 1. Decreased tonic activity. 1. The vesicular membrane is retrieved from the plasma membrane and recycled. Sequence of events involved in transmission at a  Sequence of events involved in transmission at a  typical chemical synapse typical chemical synapse
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 16

9-9-09 Synaptic Transmission I - SynapticTransmission...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online